The present application claims priority under 35 U.S.C. xc2xa7 119 to Japanese Patent Application No. 2001-007867, filed Jan. 16, 2001, entitled xe2x80x9cArrayed Waveguide Grating,xe2x80x9d and Japanese Patent Application No. 2001-142859, filed May 14, 2001, entitled xe2x80x9cArrayed Waveguide Gratingxe2x80x9d. The contents of these applications are incorporated herein by reference in their entirety.
1. Field of the Invention
The present invention relates to an arrayed waveguide grating and a method for manufacturing the arrayed waveguide grating.
2. Discussion of the Background
Recently, in optical communications, research and development of the optical wavelength division multiplexing transmission has been conducted actively for the way to dramatically increase the transmission capacity thereof, and practical applications have been proceeding. The optical wavelength division multiplexing transmission is that a plurality of lights having a wavelength different from each other are multiplexed and are transmitted, for example. Such optical wavelength division multiplexing transmission systems need optical multiplexer/demultiplexers for demultiplexing light having a wavelength different from each other or multiplexing lights having a wavelength different from each other. As one example of such optical multiplexer/demultiplexers, an arrayed waveguide grating (AWG) is known.
According to one aspect of the present invention, an arrayed waveguide grating includes at least one first optical waveguide, a first slab waveguide, an arrayed waveguide, a second slab waveguide and a plurality of second optical waveguides. The arrayed waveguide is connected to the first optical waveguides via the first slab waveguide. The arrayed waveguide includes a plurality of channel waveguides each of which has a different length. The plurality of second optical waveguides are connected to the arrayed waveguide via the second slab waveguide. A number of the plurality of channel waveguides is determined such that a crosstalk is at most a predetermined value.
According to another aspect of the present invention, an arrayed waveguide grating includes at least one first optical waveguide, a first slab waveguide, an arrayed waveguide, a second slab waveguide and a plurality of second optical waveguides. The arrayed waveguide is connected to the first optical waveguides via the first slab waveguide. The arrayed waveguide includes a plurality of channel waveguides each of which has a different length. The plurality of second optical waveguides are connected to the arrayed waveguide via the second slab waveguide. A number of the plurality of channel waveguides is determined such that optical amplitude distribution at an interface between the first slab waveguide and the at least one first optical waveguide is substantially reproduced at interfaces between the second slab waveguide and the plurality of second optical waveguides.
According to further aspect of the present invention, an arrayed waveguide grating includes at least one first optical waveguide, a first slab waveguide, an arrayed waveguide, a second slab waveguide and a plurality of second optical waveguides. The arrayed waveguide is connected to the at least one first optical waveguide via the first slab waveguide. The arrayed waveguide includes a plurality of channel waveguides each of which has a different length. The plurality of second optical waveguides are connected to the arrayed waveguide via the second slab waveguide. An optical transmittance of the arrayed waveguide grating has gaussian-shaped wavelength dependency. A number of the plurality of channel waveguides is determined such that optical amplitude distribution transmitted in the arrayed waveguide includes only main beam and first side lobes which appear on both sides of the main beam.
According to the other aspect of the present invention, an arrayed waveguide grating includes at least one first optical waveguide, a first slab waveguide, an arrayed waveguide, a second slab waveguide and a plurality of second optical waveguides. The arrayed waveguide is connected to the first optical waveguide via the first slab waveguide. The arrayed waveguide includes a plurality of channel waveguides each of which has a different length. The plurality of second optical waveguides are connected to the arrayed waveguide via the second slab waveguide. An optical transmittance of the arrayed waveguide grating has rectangular-shaped wavelength dependency. A number of the plurality of channel waveguides is determined such that optical amplitude distribution transmitted in the arrayed waveguide includes only main beam, first side lobes which appear on both sides of the main beam, and second side lobes each appearing on an outer side of each of the first side lobes.
According to further aspect of the present invention, a method for manufacturing an arrayed waveguide grating includes providing at least one first optical waveguide, providing a first slab waveguide, and providing an arrayed waveguide to be connected to the at least one first optical waveguide via the first slab waveguide. The arrayed waveguide includes a plurality of channel waveguides each of which has a different length. Further, the method includes providing a second slab waveguide, and providing a plurality of second optical waveguides to be connected to the arrayed waveguide via the second slab waveguide. A number of the plurality of channel waveguides is determined such that a crosstalk is at most a predetermined value.
According to yet another aspect of the present invention, a method for manufacturing an arrayed waveguide grating includes providing at least one first optical waveguide, providing a first slab waveguide, and providing an arrayed waveguide to be connected to the at least one first optical waveguide via the first slab waveguide. The arrayed waveguide includes a plurality of channel waveguides each of which has a different length. Further, the method includes providing a second slab waveguide, and providing a plurality of second optical waveguides to be connected to the arrayed waveguide via the second slab waveguide. A number of the plurality of channel waveguides is determined such that optical amplitude distribution at an interface between the first slab waveguide and the at least one first optical waveguide is substantially reproduced at interfaces between the second slab waveguide and the plurality of second optical waveguides.
According to further aspect of the present invention, a method for manufacturing an arrayed waveguide grating includes providing at least one first optical waveguide, providing a first slab waveguide, and providing an arrayed waveguide to be connected to the at least one first optical waveguide via the first slab waveguide. The arrayed waveguide includes a plurality of channel waveguides each of which has a different length. Further, the method includes providing a second slab waveguide, and providing a plurality of second optical waveguides to be connected to the arrayed waveguide via the second slab waveguide. The arrayed waveguide grating has an optical transmittance having gaussian-shaped wavelength dependency. A number of the plurality of channel waveguides is determined such that optical amplitude distribution transmitted in the arrayed waveguide includes only main beam and first side lobes which appear on both sides of the main beam.
According to further aspect of the present invention, a method for manufacturing an arrayed waveguide grating includes providing at least one first optical waveguide, providing a first slab waveguide, and providing an arrayed waveguide to be connected to the at least one first optical waveguide via the first slab waveguide. The arrayed waveguide includes a plurality of channel waveguides each of which has a different length. Further, the method includes providing a second slab waveguide, and providing a plurality of second optical waveguides to be connected to the arrayed waveguide via the second slab waveguide. The arrayed waveguide grating has an optical transmittance having rectangular-shaped wavelength dependency. A number of the plurality of channel waveguides is determined such that optical amplitude distribution transmitted in the arrayed waveguide includes only main beam, first side lobes which appear on both sides of the main beam, and second side lobes each appearing on an outer side of each of the first side lobes.